A roadtrain overturned, leaking sulphuric acid about 42 kilometres from Mount Isa shortly after 11am.

The last of three prime mover trailers carrying 14,000 litres of sulfuric acid tipped with at least 400 litres of the acid has spilt on to the road.

The driver was uninjured but it is believed he swerved to avoid hitting a kangaroo.

Fire and rescue crews, along with chemical experts were working to stem the flow of the spill.

There is an exclusion zone one kilometre each side of the scene.

 Mount Isa Police Inspector Brad Rix said it may take up to eight hours to clean up the spill and recover the vehicle.

“We’re urging all motorists to stay away from the area,” Inspector Rix said.

 Queensland Fire and Rescue Service (QFRS) Acting Area Commander Anthony Brewin said the rear dog trailer on a semi-trainer truck en route to Camooweal from Mount Isa had overturned.

 “The rear trailer has rolled onto its side and is spilling sulphuric acid into the table drain,” Mr Brewin said.

 He said the highway was closed while fire and rescue service staff spoke to the transport company and QFRS’s scientific branch to determine the best course of action.

 People planning to travel between Mount Isa and Camooweal were advised to stay put until the highway reopened.

"We’re looking at 98 per cent concentration and because of the leak and because it’s a corrosive substance and the truck is partly blocking the highway, until such time we can right the vehicle, this road will remain blocked.”

 Mr Brewin said the driver of the truck had escaped unharmed.

 Chemical experts were in attendance.